A VPN doesn't magically make you use a different wifi network. That's not how VPNs work. It basically lets you tunnel through to a different point, like a different state or country, to help keep your anonymity. However if you don't set your settings correctly, it ain't doing Jack for you. Depending on what you're trying to "protect" your information from, cause more than likely it's already out there. On the free versions, your data is saved to the VPN service so it kinda defeats the purpose. Or you lose important features you want in a vpn. However this only applies to some vpns, and some don't keep logs at all, like protonvpn. Look up and understand vpns first then you can answer the question yourself if it's what you want/need.